From mboxrd@z Thu Jan  1 00:00:00 1970
From: Glauber Costa <glommer@redhat.com>
Subject: Re: [RFC 4/7] change kernel accounting to include steal time
Date: Thu, 26 Aug 2010 21:33:02 -0300
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Cc: Anthony Liguori <anthony@codemonkey.ws>, kvm@vger.kernel.org,
	avi@redhat.com, zamsden@redhat.com, riel@redhat.com
To: Marcelo Tosatti <mtosatti@redhat.com>
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On Thu, Aug 26, 2010 at 08:12:40PM -0300, Marcelo Tosatti wrote:
> On Thu, Aug 26, 2010 at 06:40:36PM -0300, Glauber Costa wrote:
> > On Thu, Aug 26, 2010 at 04:14:47PM -0500, Anthony Liguori wrote:
> > > On 08/26/2010 03:28 PM, Glauber Costa wrote:
> > > >
> > > >>+   if (delta>  1000UL)
> > > >>+               touch_softlockup_watchdog();
> > > >>+
> > > >>
> > > >>This will break authentic soft lockup detection whenever qemu processing
> > > >>takes more than 1s.
> > > >This should be 10s. 1000UL is a typo.
> > > 
> > > I was wondering that when I first saw the patch..  10s is the
> > > default detection time but it's actually run time configurable so
> > > hard coding 10s is not correct.
> 
> This is not what i'm referring to. The code above will disable
> softlockup detection in case of a vcpu blocked in qemu for longer than
> softlockup threshold, which is a legitimate case.
This is equivalent to a hardware so broken it can't even send
an NMI. Not sure we should worry too much about it.